Comets: Facts And Parts
Structure and composition
The comet looks like a dirty snow ball , but is made up of 25% dust and rocks and about 75% ice. We have recored about 650 comets ; the largest nucleus that measured 42 miles! The smallest nucleus recorded was 0.3 miles. As comets nears the sun it gets smaller because the ice melts. That causes it to turn from solid to gas. The comet has two tails one of dust and one of ions. On average 5 new comets are being discovered ever year.
- Most comets are invisible except when near the sun
- Many comets are mostly found by amateur astronomers.
- Comets are usually only visible at sunrise or sun set.
- There are Chinese recordings of halleys comet going back to 240 B.C.
- Hydrogen Cloud
- Dust Tail
- Ion Tail